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The complex dynamics of calving glaciers is a major uncertainty in projecting global glacial mass loss. We present frontal ablation and ice mass change for the 38 major calving glaciers in the Patagonian icefields based on remote-sensing observations of ice-front positions, surface speeds and elevation changes. The frontal ablation from 2000 to 2019 was −24.1 ± 1.7 Gt a−1, which represents 34 ± 6% of the total ablation of the icefields. The fraction of frontal ablation was close to half in the southern icefield and about one fifth in the northern icefield. The rate of the mass loss from the icefields during the period of study was 15.2 ± 3.5 Gt a−1, which is generally explained by surface mass balance but was accelerated as a result of increasing frontal ablation. The frontal ablation and mass change values suggest surface mass balance to be −1.5 ± 0.9 Gt a−1 for the northern icefield and +11.5 ± 2.7 Gt a−1 for the southern icefield during this period. Our study demonstrates that a strong increase in frontal ablation at several glaciers drives the mass loss in the southern icefield, whereas increasingly negative surface mass balance drives the mass loss in the northern icefield.

The complex dynamics of calving glaciers is a major uncertainty in projecting global glacial mass loss. We present frontal ablation and ice mass change for the 38 major calving glaciers in the Patagonian icefields based on remote-sensing observations of ice-front positions, surface speeds and elevation changes. The frontal ablation from 2000 to 2019 was −24.1 ± 1.7 Gt a−1, which represents 34 ± 6% of the total ablation of the icefields. The fraction of frontal ablation was close to half in the southern icefield and about one fifth in the northern icefield. The rate of the mass loss from the icefields during the period of study was 15.2 ± 3.5 Gt a−1, which is generally explained by surface mass balance but was accelerated as a result of increasing frontal ablation. The frontal ablation and mass change values suggest surface mass balance to be −1.5 ± 0.9 Gt a−1 for the northern icefield and +11.5 ± 2.7 Gt a−1 for the southern icefield during this period. Our study demonstrates that a strong increase in frontal ablation at several glaciers drives the mass loss in the southern icefield, whereas increasingly negative surface mass balance drives the mass loss in the northern icefield.

Measuring glacier calving magnitude, frequency and location in high temporal resolution is necessary to understand mass loss mechanisms of ocean-terminating glaciers. We utilized calving-generated tsunami signals recorded with a pressure sensor for estimating the calving flux of Bowdoin Glacier in northwestern Greenland. We find a relationship between calving ice volume and wave amplitude. This relationship was used to compute calving flux variation. The calving flux showed large spatial and temporal fluctuations in July 2015 and in July 2016, with a mean flux of 2.3 ± 0.15 × 105 m3 d−1. Calving flux was greater during periods of fast ice flow, high air temperature, and at low/falling tide, indicating the importance of increased longitudinal strain due to glacier acceleration and/or submarine melting at the calving front. Long-term measurements with the method introduced here are promising for understanding the complex interplay of ice dynamics, melting and calving at glacier fronts.

Measuring glacier calving magnitude, frequency and location in high temporal resolution is necessary to understand mass loss mechanisms of ocean-terminating glaciers. We utilized calving-generated tsunami signals recorded with a pressure sensor for estimating the calving flux of Bowdoin Glacier in northwestern Greenland. We find a relationship between calving ice volume and wave amplitude. This relationship was used to compute calving flux variation. The calving flux showed large spatial and temporal fluctuations in July 2015 and in July 2016, with a mean flux of 2.3 ± 0.15 × 105 m3 d−1. Calving flux was greater during periods of fast ice flow, high air temperature, and at low/falling tide, indicating the importance of increased longitudinal strain due to glacier acceleration and/or submarine melting at the calving front. Long-term measurements with the method introduced here are promising for understanding the complex interplay of ice dynamics, melting and calving at glacier fronts.

Calving plays a key role in the recent rapid retreat of glaciers around the world. However, many processes related to calving are poorly understood since direct observations are scarce and challenging to obtain. When calving occurs at a glacier front, surface-water waves arise over the ocean or a lake in front of glaciers. To study calving processes from these surface waves, we performed field observations at Glaciar Perito Moreno, Patagonia. We synchronized time-lapse photography and surface waves record to confirm that glacier calving produces distinct waves compared with local noise. A total of 1074 calving events were observed over the course of 39 d. During austral summer, calving occurred twice more frequently than in spring. The cumulative distribution of calving-interevent time interval followed exponential model, implying random occurrence of events in time. We further investigated wave properties and found that source-to-sensor distance can be estimated from wave dispersion within ∼20% error. We also found that waves produced by different calving types showed similar spectra in the same frequency range between 0.05–0.2 Hz, and that the amplitude of surface waves increased with the size of calving. This study demonstrates the potential of surface-wave monitoring for understanding calving processes.

Calving plays a key role in the recent rapid retreat of glaciers around the world. However, many processes related to calving are poorly understood since direct observations are scarce and challenging to obtain. When calving occurs at a glacier front, surface-water waves arise over the ocean or a lake in front of glaciers. To study calving processes from these surface waves, we performed field observations at Glaciar Perito Moreno, Patagonia. We synchronized time-lapse photography and surface waves record to confirm that glacier calving produces distinct waves compared with local noise. A total of 1074 calving events were observed over the course of 39 d. During austral summer, calving occurred twice more frequently than in spring. The cumulative distribution of calving-interevent time interval followed exponential model, implying random occurrence of events in time. We further investigated wave properties and found that source-to-sensor distance can be estimated from wave dispersion within ∼20% error. We also found that waves produced by different calving types showed similar spectra in the same frequency range between 0.05–0.2 Hz, and that the amplitude of surface waves increased with the size of calving. This study demonstrates the potential of surface-wave monitoring for understanding calving processes.